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Discovers that the pendant drop method, used in an ultrahigh vacuum drop tube, allowed determinations of the liquid surface tension of the refractory metals. Introduction to the liquid surface tension; Analysis of droplets formation; Conclusion.

A thermodynamic approach to homogeneous crystalline nucleation in binary liquid alloys is presented, which is based on a two-step mechanism for critical embryo formation. It postulates that suitable concentration fluctuations in the undercooled liquid state can provide favoured sites for nucleation. Thus, a distinction is operated between local chemical order fluctuations and structure fluctuations, as opposed to the classical nucleation theory approach. To quantify the importance of concentration fluctuations, the proposed mechanism is applied to binary liquids exhibiting a tendency towards phase separation. The energy required to form a relevant fluctuation in the liquid, prior to nucleation, is calculated as a function of the undercooling amount. Furthermore, the ratio between the population of relevant fluctuations and that of critical nuclei is assessed statistically: the probability for a fluctuation to become a critical embryo increases with the amount of undercooling. Finally, the two-step mechanism for nucleation is supported from a kinetic point of view. [ABSTRACT FROM AUTHOR]

• Current molecular methods have enhanced HABs/CHABs biomonitoring but have limitations. • CRISPR/Cas is a powerful and ultrasensitive molecular tool for molecular diagnosis. • Cas12/Cas13 effectors have potential as next-generation biomonitoring tools. • Multiple genes in bloom forming species could be targetted for CRISPR/Cas-based biomonitoring. Research on harmful algal and cyanobacterial blooms (HABs and CHABs) has risen dramatically due to their increasing global distribution, frequency, and intensity. These blooms jeopardize public health, ecosystem function, sustainability and can have negative economic impacts. Numerous monitoring programs have been established using light microscopy, liquid chromatography coupled to mass spectrometry (LC-MS), ELISA, and spectrophotometry to monitor HABs/CHABs outbreaks. Recently, DNA/RNA-based molecular methods have been integrated into these programs to replace or complement traditional methods through analyzing environmental DNA and RNA (eDNA/eRNA) with techniques such as quantitative polymerase chain reaction (qPCR), fluorescent in situ hybridization (FISH), sandwich hybridization assay (SHA), isothermal amplification methods, and microarrays. These have enabled the detection of rare or cryptic species, enhanced sample throughput, and reduced costs and the need for visual taxonomic expertise. However, these methods have limitations, such as the need for high capital investment in equipment or detection uncertainties, including determining whether organisms are viable. In this review, we discuss the potential of newly developed molecular diagnosis technology based on Clustered Regularly Interspaced Short Palindromic Repeats/Cas proteins (CRISPR/Cas), which utilizes the prokaryotic adaptative immune systems of bacteria and archaea. Cas12 and Cas13-based platforms can detect both DNA and RNA with attomolar sensitivity within an hour. CRISPR/Cas diagnostic is a rapid, inexpensive, specific, and ultrasensitive technology that, with some further development, will provide many new platforms that can be used for HABs/CHABs biomonitoring and research. [Display omitted] [ABSTRACT FROM AUTHOR]

Presents the Grenoble drop tube first experiments and results on pure W and Re droplets. Amounts of undercooling achieved; Liquid-solid interfacial energy derived from the experiments.

We evaluated the technique of airway anaesthesia using atomised lidocaine for awake oral fibreoptic intubation in morbidly obese patients using two doses of local anaesthetic. Morbidly obese patients were allocated to receive either 2% or 4% lidocaine (40 ml) for oral airway anaesthesia using an atomiser with high oxygen flow. Patients were carefully sedated using midazolam and fentanyl. Outcomes included patient tolerance to airway manipulation, haemodynamic parameters, and serial plasma lidocaine concentrations. In all, 27 patients were enrolled in the study (2% cohort n = 14, 4% cohort n = 13). Patient characteristics and time for topicalisation and airway management were similar. Haemodynamic parameters did not change significantly. Tolerance to insertion of the Ovassapian airway, bronchoscopy, and tracheal tube positioning was excellent (12 vs 12 patients, 12 vs 12 patients, and 8 vs 12 patients had no response, respectively, 2% vs 4%). Differences did not reach statistical significance. Peak plasma lidocaine concentration was significantly lower in the 2% group (2.8 (0.8) μg.ml−1 compared with 6.5 (1.0) μg.ml−1, p < 0.05). Airway anaesthesia using atomised lidocaine for awake fibreoptic intubation in the morbidly obese is efficacious, rapid, and safe. Compared with 4% lidocaine, the 2% dose provides acceptable intubating conditions in most cases and produces lower plasma lidocaine levels. [ABSTRACT FROM AUTHOR]

Airway anaesthesia using atomised lidocaine for awake oral fibreoptic intubation in morbidly obese patients was evaluated using two doses of local anaesthetic. In this randomised, blinded prospective study, 40 ml of atomised 1% ( n = 11) or 2% ( n = 10) lidocaine was administered with high oxygen flow as carrier. Outcomes included time for intubation, patient tolerance to airway manipulation, haemodynamic parameters, the bronchoscopist’s overall satisfaction, and serial serum lidocaine concentrations. Patients receiving lidocaine 1% had a longer mean (SD) time from the start of topicalisation to tracheal tube cuff inflation than those receiving lidocaine 2% (8.6 (0.9) min vs 6.9 (0.5) min, respectively; p < 0.05). Patients in the 1% cohort demonstrated increased responses to airway manipulation (p < 0.0001), reflecting lower bronchoscopist’s satisfaction scores (p < 0.03). Haemodynamic responses to topicalisation and airway manipulation were similar in both groups. Peak plasma concentration was lower in the 1% group (mean (SD) 1.4 (0.3) and 3.8 (0.5) μg.ml−1, respectively; p < 0.001). Airway anaesthesia using atomised lidocaine for awake oral fibreoptic intubation in the morbidly obese is efficacious, rapid and safe. Compared with lidocaine 1%, the 2% dose provides superior intubating conditions. [ABSTRACT FROM AUTHOR]

Abstract: The measurement of the surface tension of liquid silicon has a long history with many results but no general agreement between them. Two values at the melting temperature are cited in reviews (749 and 827mN/m [N. Eustathopoulos, E. Ricci, B. Drevet, Note Technique DEM No. 97/58, CEA, 1997]) but there are few arguments to determine the correct one. In the present study, new data for the surface tension obtained with the analysis of characteristic frequencies of a levitating drop are presented. The effect of oxygen and nitrogen are also considered. These data are compared with former data obtained with contactless techniques. The most recent surface tension values obtained with drop weights ranging on two orders of magnitude and environments of different natures (argon, hydrogen and vacuum) show excellent agreement (within a 1.5% margin) at temperatures between 1350K and 2400K. The comparison of these data to others obtained with different techniques, reveal a good agreement, except those obtained with the sessile drop technique on some supports like BN, SiO2 and MgO. However, these special cases may be connected with the reactivity of silicon with these supports. [Copyright &y& Elsevier]